Ink jet printing is a non-impact means of producing a pattern of ink droplets which can be used to record digital information. To make a hard copy, the droplets are deposited onto a transparent, translucent, or opaque support such as film, vellum or paper. Ink jet printers have been used for many years to make monochrome hard copy from computers. A rapidly-growing use of ink jet printers is to generate subtractive color images using a three- or four-color process. The resultant hard copy can be viewed by transmitted light using an overhead projector (transparent film); by transmitted light using a diffuse illuminator (translucent film); or by reflected light (opaque support).
In subtractive continuous tone silver halide color photography, color images are produced by the superposition of three primary continuous-tone color-intensity-graduated recording layers. In non-continuous tone ink jet color printing, use is made of microscopic superposed color-separated dots (so-called halftone images) to create an impression to the viewer of an intensity graduated image. The proper hue, size, and degree of coalescence and mixing of the primary color dots--cyan, magenta, yellow and black--are necessary for the faithful reproduction of color on the recording medium. Accurate ink jet color image recording thus requires a high degree of cooperation between the ink jet color separation pulses, the ink dyestuffs, and the ink acceptor material.
An ink acceptor material should be capable of accepting the droplets readily and allowing them to coalesce, yet should achieve color isolation and separation with high chroma and pure hue without image edge distortions due to poor registration, bleeding, feathering, or other image quality defects. Acceptor materials for colored inks currently available, however, suffer from rapid fading of one or more of the dyestuffs upon exposure to light. Furthermore, currently available ink acceptor materials can be degraded easily by repeated handling or contact with moist objects. As a consequence of such contact, the moist object often becomes stained with the dyestuffs. Also, because the usual aqueous ink jet inks have relatively low volatility, imaged acceptor materials are typically still wet with the aqueous ink vehicle when emerging from an ink jet printer. Images are then most vulnerable and can be altered by smudging or blocking (print stacking). Thus, there is a need for an ink acceptor material capable of rendering ink jet images which dry rapidly, are water-resistant and light stable, can be handled and stacked without damage to the printing or images, and which have good layer clarity and good sheet feeding properties in ink jet printers. The materials of the invention meet these needs.